The latest and greatest version of the M16 is the M16A5 “Designated Marksmen Rifle.” It looks like an A4, but it has a better barrel, better trigger, and an ACOG 4x sight on the flat top.
Snipers are reporting first round kills at 800 yards when firing the 77 grain Black Hills ammo.
Doesn’t get much better than that.
BTW, tricked out AR-15s in 5.56mm have been cleaning up the thousand yard competitions for years now.
“BTW, tricked out AR-15s in 5.56mm have been cleaning up the thousand yard competitions for years now.”
I don’t doubt that a properly built and tuned AR-15 can hit a target at 1000 yards, but I don’t think a .22 caliber bullet carries enough energy at that distance to be useful.